Blender + Ni Mate (Mocap Animation)
I had the same problem and I found a solution to it. It's a function called "Bake Action". 

Select all the kinect-empties, select the armature you want to have the action on and either use the space bar to search for "bake action" or click the button at the side menu under "Animation". In the pop-up window deselect "Only Selected" and select "Visual Keying", "Clear Constraints" and "Pose". Press "Okay" and your selected armature should now have an Action that is suitable to be played in Unity.

Source for Action baking: https://www.blend4web.com/en/forums/topic/271/